Would you like to integrate more meaningful digital resources into your STEM curriculum, but have no budget to do so? CK-12 is an excellent Open Educational Resource that is free and easy to use. Digital resources include PLIX interactives and simulations, adaptive practices, study guides, and FlexBook digital textbooks. CK-12 FlexBooks are online platforms for assembling, authoring, and distributing interactive, multi-modal educational content. FlexBooks can be downloaded and used as-is, or can be customized by teachers to match their students’ learning styles and their school’s curricula. Inside each book, chapters can be rearranged, added, removed, and edited. FlexBooks can be shared, for free online, by email, or on platforms including Facebook and Twitter or through Google Classroom. All FlexBooks are aligned to national and state curriculum guidelines, Common Core Standards, and Next Generation Science Standards.